RALEIGH, N.C. -- A federal report says understaffing was so bad at a North Carolina prison where four employees were killed during the deadliest breakout attempt in state history that workers cut corners in ways that created opportunities for mayhem.

The security assessment of Pasquotank Correctional Institution by the National Institute of Corrections was released Thursday. The arm of the U.S. Justice Department was called in after October's deadly escape attempt.

The report says workers at the Elizabeth City prison were forced to maintain oversight and prison services despite one in four jobs being vacant, adding they consequently grew complacent about security measures. It adds understaffed prison workers fell short on conducting required strip searches, keeping track of tools and hazardous chemicals, and finding hiding places outside the view of prison video cameras.